Seized stop tap

[prophet]

Not urgent in any way but cannot unseize this stop tap.

I loosened the packing box and sprayed WD 40. Heated it up with a heat gun and sprayed some more. Repeated a number of times but can't get it to turn at all.

Any tips please?

 

[Deleted member 267285]

Which way are you turning it? If there’s any play in it, you could always try turning it anti-clockwise then clockwise to close. Careful though, it looks like one of those heads which will separate if applying too much pressure on it.

 

[prophet]

Tried turning both ways but there's zilch play.
Wouldn't want to apply any more pressure than I have already.

 

[Deleted member 267285]

Just re-read, not entirely sure what temperature a heat gun will generate. Anyway, if the head does come off, then you could use an adjustable spanner to operate until you could renew.

 

[prophet]

My heat gun's a Wagner Furno 750, 50 - 630 centigrade.

Was thinking of buying a cheap car wheel wrench, cutting a slot in the end to get a purchase on the tap and trying to turn it through that good, balanced leverage.

 

[denso13]

Was thinking of buying a cheap car wheel wrench, cutting a slot in the end to get a purchase on the tap and trying to turn it through that good, balanced leverage.

The real thing is less than a fiver, https://www.toolstation.com/stop-cock-key/p62757

 

[prophet]

Good call.
Off to Toolstation first thing in the morning it is then.

 

[Agile]

Don't rush too quickly.

Old one seems to be soldered.

New one is likely to be 15mm compression!

 

[charlie275]

Was thinking of buying a cheap car wheel wrench, cutting a slot in the end to get a purchase on the tap and trying to turn it through that good, balanced leverage.

Torque is what can shear a seized bolt where an impact driver would free it. I would rather hit one end of that good, balanced leverage, with a two pound hammer.

 

[dilalio]

Try Plus Gas or some other release agent and treat it over a few hours or days.
Wd40 doesn't always work as it's more for water displacement rather than penetrating. If you have access to the external stop cock then isolate that first. Gentle pressure in both directions to encourage it to ease.

 

[Madrab]

If the tap itself is seized and wont budge then you may need to crack the headgear off it and see if you can free up the internals, on the bench. You do need to be careful though as the pipework can go before the headgear does. As mentioned, shut down the mains to it first.

Is there an option to cut a new tap in further downstream?

 

[Mike13]

Chances are it was wound fully open and left like that, try some mild descaler too?
I always open fully, then immediately wind back in a 1/4 turn, makes no difference to max flow and stops the thread from galling solid.

 

[prophet]

Appreciate all the responses folks.
Taking into account...

1. that there's no urgency
2. doing a bit more reading. This is an interesting piece https://www.frenchcarforum.co.uk/forum/viewtopic.php?f=8&t=3700
3. Dilalio's alusion to patience

...I'll do a bit more heating, spraying and cooling throughout today attempting to turn it with this which I'm off to get in a minute - Mini crutch key
along with a can of Plus Gas from Eurocarparts (Only £5.99)

 

[prophet]

So, after multiple heating, spraying with PlusGas and cooling cycles I've so far only managed to break off the handle.

I suppose I'll keep going with the heat, spray, cooling cycle and try to turn with stilsons...or give up and get a pro in.

 

[JohnD]

If the tap itself is seized and wont budge then you may need to crack the headgear off it and see if you can free up the internals, on the bench ...

provided you can isolate the supply upstream, that's what I'd do

your existing valve does not look very old, if you unscrew the innards you can probably buy a new tap and swap the working parts into the new shell. Taking the new one apart will teach you how it works and comes apart.